Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Components of Property and Equipment

Depreciation expense is computed using the straight-line method over the following useful lives:

Computer hardware	2 to 3 years
Computer software	2 to 5 years
Furniture and equipment	5 years
Leasehold improvements	Term of lease, 5 years maximum

Property and equipment consisted of the following (in thousands):

	December 31,
	2017			2016
Computer hardware	$	171,515		$	170,746
Computer software	376,761			374,490
Furniture and equipment	102,424			100,472
Leasehold improvements	148,764			133,541
Other	9,907			9,993
Property and equipment, cost	809,371			789,242
Accumulated depreciation	(664,484		)	(627,733		)
Property and equipment, net	$	144,887		$	161,509